JPH0245671B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method of treating guayule plant material. More particularly, it relates to a process that includes a volatilization and heating step to convert and recover resinous materials, extracts and resins from guayule plants.

Parthenium argentatum Gray, a guayule plant that grows primarily in the Southern United States and Mexico
is known as a potential domestic source of rubber and organic chemicals. For example, Consejo Nacional de
Ciencia y Technologia, SalTillo,
The book “Guayule Reencuentro en el Desierto” published by Coahuila, Mexico (1978) and
Federal Emergency Management Agency;
Washington, DC, 20472, Volume I, No. 4,
See the magazine "Emergency Management Agency" published by 1981, pp. 4-9. Rubber and other useful organic materials can be obtained from guayule by known methods including milling the guayule material, extraction and/or water flotation.

Although much attention has been given to the recovery and processing of elastomeric materials from guayule, less attention has been paid to the utilization of other organic materials that can be obtained from these sources, such as resins. Since large quantities of rubber will likely be recovered from guayule in the future, it is clear that large quantities of other guayule organic products will also become available, such as oils and resins. Therefore, methods of processing the above guayule products to convert these other guayule products into useful substances such as liquids and gases that can be used as fuels, lubricants and chemical feedstocks are of increasing interest. are doing. The present invention achieves these goals.

Guayule resin, i.e., these components of the guayule plant obtained when the guayule plant itself or the resinous gum produced therefrom is extracted with an organic oxygenated solvent such as acetone, ethyl acetate, etc., are described as a source of fats and essential oils. Ta. (for example,
(See U.S. Patent Nos. 2,744,125 and 2,572,046).
Steam treatment of guayule plant material is Haagen−
Smit et al., J.Amer.Chem, Soc., 662068
(1944). The book "Guayule" mentioned above describes the development of varnishes and adhesives from guayule resin.

Includes papers by Belmares and Jimenez.

U.S. Patent No. to Buchanan and Balman
Nos. 4,136,131 and 4,159,903 describe improved methods of treating guayule plants to provide rubber and enhance rubber formation in the plants.

The use of thermal and catalytic techniques to process various petroleum fractions to produce useful liquid and gaseous products is well known. For example, The Chemistry of Petroleum, edited by Brooks et al.
Hydrocarbons, Reinhold Publishing Corp.
NY (1955), especially Volume, 22, 23, 24 and
See Chapter 28. However, no references were found for the treatment of extracts, resins or feeds derived from guayule or similar sources.

Processing the guayule plant material to provide a resinous extract and then volatilizing at least a portion of the extract into a form to obtain a vapor, with or without any intermediate steps; It has been found that useful liquid and gaseous products can be produced from guayule plant material by fragmentation by heating. Such fragmentation is often carried out under the conditions described above using petroleum cracking catalysts such as alumina,
This occurs in the presence of a catalyst comprising silica and at least one metal. Fragments can be recovered by cooling and/or absorption of the effluent to provide organic liquids and gases that are useful as, for example, fuels, lubricants, and chemical feedstocks. These organic liquids and gases are also within the scope of this invention.

Among the plant materials that give resinous materials that can be used in the present invention are a number of rubber and related hydrocarbon-producing species, such as guayule itself, Rabbit-Brush, etc.
(Crysothamnus nauseousus), Rubbervine (Cryptostegia grandiflora), Milkweeds (Asclepias)
incarnata, sublata, syriaca, etc.), Goldenrods (Solidago altissima,
graminifolia, leavenworthii, rigida, etc.), Sowthistles (Sonchus arvensis)
oleraceous et al), Rosin oglema (Rosin
Weeds) (Silphium species), Mountain Mints (Pycnanthemum species)
and Cacalia atriplicifolia (Cacalia
guayule and guayule-like plants, including atriplicifolia. Many other products, especially Asteraceae, which also produce organic extracts and resins,
The families Euphorbiaceae, Labiatae, and Moraceae are known. Resinous materials from these can also be advantageously processed in the present invention.

The plant materials described above can be processed by a number of known methods to provide resinous materials for use in the present invention. Typically, the plants are ground in various types of mill equipment such as hammer mills, roll mills, stone mills, ball mills, pulp mills, and then extracted or subjected to water flotation. This often results in a resinous material that does not contain much rubber (generally less than 40% rubber, often 20%
% or less than 10% or less than 5% rubber).

The invention thus provides: (a)(i) treating guayule and/or related plants in a manner known per se to obtain a resinous material;
Here, the related plants include rabbit brassica (Crysothamnus nauseousus), rubber bean (Cryptostegia grandiflora), milkweed (Asclepias incarnata,
sublata, syriaca), goldenrod (Solidago altissima, graminifolia,
leavenworthii, rigida), Sonchus
arvensis oleraceous et al), Silphium species, Mountain mint (Pycnanthemum species) and Cacalia atoprisifolia.
atriplicifolia), and the following (a)(ii), (a)
Steps (iii) and (a)(iv): (a)(ii) removing the solvent from the resinous material to obtain a resinous extract; (a)(iii) removing the resinous material or the resinous extract; recovering the rubber from the extract and leaving a resin; (a)(iv) supplying the resinous material, the resinous extract or the resin with an organic carrier which is an aromatic hydrocarbon having a boiling point higher than 80°C; or without performing any of steps (a)(ii), (a)(iii) and (a)(iv), (a)′ The resinous substance, the resinous extract, the resin,
(b) extracting at least a portion of the water-extracted resinous material, resinous extract, resin, feed or mixture thereof by methods known per se; (c) vapor b is vaporized in a heating chamber, (i) at a temperature between 200 and 800°C under ambient pressure to obtain a vapor of 0.001
2 hours, or (ii) 0.001 to 0.5 hours at 200 to 250° C. from 50 mm Hg to ambient pressure in the presence of at least one oil fluid cracking catalyst consisting of alumina, silica and at least one other metal.
heating to decompose at least a portion thereof; (d) removing the decomposition product from the chamber as an effluent; and (e) recovering the decomposition product from the effluent.

In the previous description of the invention, resinous material refers to material from the treatment of guayule plants by any suitable technique. Resinous materials include, but do not necessarily include, in addition to resin, gums, solvents, and other naturally occurring contaminants. The resinous extract contains all the components of the resinous material except the solvent (less than 2%), while the resin is substantially free of solvent and gum (less than 2% of each). Organic solvents are oxygenated solvents such as alcohols, ketones, esters or ethers of 1 to about 8 carbon atoms (or mixtures of two or more thereof) or carbonized solvents having a boiling range of about 50-150°. It can be a hydrogen solvent such as hexane, heptane, octane, nonane or mixtures thereof.
Aromatic solvents such as benzene, toluene, etc. can be used alone or in mixtures with one another. Methods of solvent extraction of pulverized guayule plant material are known and previously described, for example, in US Patent Application Nos. 149,862, 298,447 and 307,405. The portions pertinent to these uses are incorporated herein by reference for their disclosures relating to processing guayule plant material to provide resins and resinous materials.

As noted, resinous substances are often obtained in the form of solutions. This solution can be directly volatilized to give vapor as described below. Optionally, and more typically, it is first treated to remove the solvent from the mixture to provide a resinous extract. This solvent removal can be accomplished by conventional methods such as distillation, steam distillation, adsorption, absorption, extraction (first solvent to second solvent but not extractant). Whatever technique or combination of techniques is used, a resinous extract is produced which is further processed to recover any rubber present and leave a resin (generally containing less than 2% rubber). Methods for recovering rubber from resinous materials and extracts are known and include extraction with rubber solvents, water flotation, and combinations thereof. A detailed description of such a process is given, for example, in US Patent Application No. 149,862, which is hereby incorporated by reference for its disclosure regarding the recovery of guayule gum. Removal of such rubber leaves a resin as a residue, which can optionally be diluted by adding an organic carrier. Such carriers are added to either the resinous material, extract or resin and serve to reduce its viscosity, thereby facilitating its handling and further processing. Usually the carrier is an aromatic hydrocarbon with a boiling point above 80°C. Typical organic carriers include xylene, various substituted naphthalenes, especially mono- and dimethylnaphthalenes. Addition of carriers to resinous materials, extracts, and/or resins provides a relatively fluid feed for the next step in the process that is easily handled, pumped, and transferred between processing units. .

The steps and sub-steps described above can be combined in various ways and any of a variety of steps can be used or not dictated by the particular circumstances, as will be apparent to those skilled in the art. Often this will depend on the technique used to process the guayule plant to provide the resinous material. Sometimes the resinous material is rubber-free (ie, it contains less than 2% rubber). In such examples, optional step (a)(iii) is not used. In other cases, the resinous material is in a solvent and optional step (a)(iii) is included.
For example, the organic solvent can be an alcohol, ketone, ester or ether of from 1 to about 8 carbon atoms as described above, and step (a)(iii), recovery of the gum from the resinous extract, is omitted. It will be destroyed. Frequently in such instances the organic solvent is an alcohol such as methanol, propanol or isopropanol or a ketone such as acetone, methyl ethyl ketone or methyl isobutyl ketone or mixtures thereof. In other circumstances, a hydrocarbon solvent can be used, such as a C _5-8 hydrocarbon, and optional step (a)(iii) is carried out. In still other cases, solvent (a)(iii) is removed and the carrier
Either or both of the optional steps of adding (a)(iv) are effective. In still other cases, a carrier is used, such as an aromatic hydrocarbon having a boiling point above about 80°.

The next step in the process of the invention, step (b), consists of volatilizing at least a portion of the resinous material, extract, resin feed or mixture thereof to provide steam. Those skilled in the art are aware of suitable means to achieve this volatilization. Since the invention is not limited to specific volatilization means, details are not cited here. In typical embodiments, step (b) is accomplished in a preheater where at least about 30% of the material to be volatilized is volatilized.

Temperatures of approximately 200°-900° are used. Vacuum (about 50
Pressures ranging from mmHg) to atmospheric pressure are widespread.

The vapor provided by the volatilization step (b) is then heated in a heating chamber at a temperature, pressure and time sufficient to cause some of it to decompose, ie form low molecular weight molecules.
This decomposition is manifested by a decrease in the boiling range of the steam. Here too, any suitable means for achieving the desired conditions in the heating chamber can be used. An oven is typically provided. The oven can conveniently be fueled by a portion of the effluent from the process. The temperature in the heating chamber, when combined with the prevailing pressure and residence time of the vapor therein, is sufficient to cause some of the volatilized material to decompose. Typically this temperature will be in the range of about 200-800°. The residence time typically varies between about 0.001-2 hours and the pressure varies from ambient (atmospheric) pressure to about
Pressures vary as low as 50mm of mercury. Temperatures in the range of 200 DEG -750 DEG have been found to be particularly useful in the presence of catalysts such as the petroleum cracking catalysts described below. Residence times of about 0.001-0.5 hours can be used.

As shown, at least one catalyst, typically a petroleum cracking catalyst, is present during heating step (c). Many such catalysts are known to those skilled in the art and can be used in the present invention, which is not limited to a particular type of catalyst. Typical catalysts consist of alumina, silica and at least one metal. The use of a catalyst has been found to allow lower heating temperatures and shorter residence times, and has been found to provide an increase and/or variation in the yield and distribution of the products produced by the process of the invention. . Particular catalysts that can be used in the present invention include fluidized cracking catalysts.
Dutch AKZO Chemie Nederland named KETJEN CAT series MZ-7X
It is an alumina catalyst sold by Company.
This catalyst is described more fully below. Variations in this regard can and will be made by those skilled in the art, as the invention is not limited to particular catalysts, or even the presence of catalysts.

After residence in the heating chamber for a desired temperature, pressure and time sufficient to decompose at least a portion of the vapor, the decomposed products are removed from the chamber (step d) and recovered (step e). Means for accomplishing these steps are known to those skilled in the art and need not be described in detail. Typically, recovery is accomplished by cooling and/or absorption in a solid or liquid absorbent. Typically, the decomposition product is removed as an effluent, which is cooled to about 0°, more typically about 0-30°, to condense the liquid fraction. The gaseous fraction is then trapped, for example by a floating gas bottle or other conventional means. Cooling of the decomposed vapors to about 0° often yields about 25-75% organic liquid (based on the weight of the vapor). This fluid will contain fractions varying from light gasoline to heavy gas oil as defined by the appropriate ASTM standard. By adjusting such heating chamber parameters, such as temperature, residence time, pressure and catalyst, variations in product distribution, such as providing feedstock for lube oil fractions and chemical processing, are achieved.
Among the feedstocks are gaseous fractions containing unsaturates such as ethylene, propylene isomeric butylene mixtures, pentane, butadiene and similar products.

The liquid produced by cooling and/or absorbing the effluent of the process of the invention to about 0-30° can be further processed by physical and/or chemical means to produce liquid fuels and liquid lubricants, semi-solids, etc. It may be further processed by physical and/or chemical means to provide a solid grease, liquid, gaseous or solid chemical feedstock. These materials can be used for such purposes alone or in combination with other materials obtained from more conventional sources.

An even better understanding of the invention can be obtained with reference to the Examples below. In the examples, all percentages and parts are by weight and all temperatures are in degrees Celsius, and throughout the specification and claims, temperatures are also in degrees Celsius.

EXAMPLE A microactive catalyst test device is used to conveniently illustrate the invention. The method and apparatus are essentially the same as ASTM D-3907-80 (25 copies, 978 pages, entitled “Fluid Cracking Catalyst by Micro Activity
During this example, vapors from the guayule resin pass through a cracking catalyst placed in a fixed bed reactor. The cracked liquid products of the effluent are collected and The gaseous and fixed products are analyzed as such. The conversion expressed as a percentage is the difference between the weight of the feed and the unconverted product. After passage of the feed over the catalyst,
The reactor is purged with nitrogen and the organic material stripped with this nitrogen purge is added to the product receiver. The catalyst is then removed from the reactor heating chamber and the amount of carbonate thereon is determined.
Non-condensable products in the effluent are recovered by replacing appropriate liquids in a gas bottle.

The condensed fraction (collected at essentially 0°) is weighed and analyzed by gas chromatography. Non-condensable gases are also analyzed by chromatography. The condensed product is
ASTM D2887, entitled “Test for Boiling Range
Distribution of Petroleum Fractions by Gas
The results in the following examples are for light gasoline (representing about 95% of the sample distilling at or below 100°), heavy gasoline (fraction distilling at 100-216°). , and expressed as percentage conversion to light cycle oil (fraction distilling at 216-347°).The catalyst used in these examples had the designation Fluid Cracking Catalyst KETJEN CAT,
Under the series MZ−7X, AKZO CHEMO
Available from NEDERLAND. This catalyst is a low surface area cracking catalyst with excellent attrition properties. Its chemical composition (on a percentage dry basis) is: Alumina (Al ₂ O ₃ ) 30 Sodium oxide (Na ₂ O) 0.3 Iron (Fe) 0.3 Sulfate (SO ₄ ) 0.1. Physical properties g/ml, 0.80; surface area,
m ² /g150; pore volume, ml/g, 0.28. The guayule resin was obtained by acetone deresination of freshly harvested and ground guayule essentially using the method described in US Patent Application No. 149,862. The above patents are incorporated herein by reference for their disclosures on the isolation and recovery of guayule resin. The resin is diluted with 1-methylnaphthalene (50%) to reduce its viscosity. A correction of the results is made for the presence of 1-methylnaphthalene diluent. The methylnaphthalene/guayule resin feed was as described above.
Processed using ASTM methods. The conversion of resin to product is calculated to be 46.6%. Material balance accounts for 99.3% of preparation. The product distribution of the decomposition products is summarized in the table. Since the mass balance in the experiment is high (99.3%), the weight percentage value is adjusted to 100%. This is a non-condensable gas,
The general distribution of the decomposed resin as liquid and fixed is easily revealed. Note that the hydrogen gas value is included in the total noncondensable gas value and that the "coke on catalyst" value is also included in the "total coke" value.

Table Microactivity Test for Guayule Resin Product Distillation Weight % Conversion 46.6 Mass Balance 99.3 Total Noncondensable Gas 11.7 Hydrogen Gas 0.02 Light Gasoline 9.6 Heavy Gasoline 15.9 Light Cycle Oil 51.5 Residue ^* 1.7 Total Coke 9.6 Coke on Catalyst 3.2 *Residue values for gas chromatography method It will be noticed from the data in the table that 11.7% of the decomposed guayule resin appears as a non-condensable gas with 0.02% fixed as hydrogen.
This shows that it is possible to obtain gaseous fuel by heat treatment of guayule resin. Highly branched organic compounds will be present in the resin and would be expected to yield useful fuel products during heat treatment. The total amount of cracked guayule resin appears as liquid fractions, such as light gasoline (9.6%), heavy gasoline (15.9%), and light cycle oil (51.5%). This demonstrates the production of useful products from heat treatment of guayule resin.

The non-volatile residue and resulting coke values are caused by the presence of 4.5% of the water-soluble fraction of the guayule resin used to produce the feed. The crude resin is first treated with water to remove this fraction and minimize the amount of coke formation. This is not undesirable in all cases since a small amount of coke on the catalyst can be beneficial to the overall process in some respects. The catalyst can be regenerated, for example by air purge to burn off coke to volatile carbon dioxide, a well known highly exothermic reaction resulting in heating of the catalyst bed. Such a process lowers process costs and at the same time makes coke available.

The examples described above are presented for illustrative purposes only and are not intended to limit the scope of the invention. Variations in the equipment and processes used, as well as the feeds and conditions, will be apparent to those skilled in the art and are within the scope of the invention.

Claims (1)

Claims: 1 (a)(i) Guayule and/or related plants are treated in a manner known per se to obtain a resinous material, wherein the related plants are rabbit brassica (Crysothamnus nauseousus). ), rubber bean (Cryptostegia grandiflora),
Milkweed (Asclepias incarnata,
sublata, syriaca), goldenrod (Solidago altissima, graminifolia,
leavenworthii, rigida), Sonchus
arvensis oleraceous et al), Silphium species, Mountain mint (Pycnanthemum species) and Cacalia atoplicifolia (Pycnanthemum species).
atriplicifolia), and the following (a)(ii), (a)
Steps (iii) and (a)(iv): (a)(ii) removing the solvent from the resinous material to obtain a resinous extract; (a)(iii) removing the resinous material or the resinous extract; recovering the rubber from the extract and leaving a resin; (a)(iv) supplying the resinous material, the resinous extract or the resin with an organic carrier which is an aromatic hydrocarbon having a boiling point higher than 80°C; or without performing any of these steps (a)(ii), (a)(iii) and (a)(iv); ' The resinous substance, the resinous extract, the resin,
(b) extracting at least a portion of the water-extracted resinous material, resinous extract, resin, feed or mixture thereof by methods known per se; (c) vapor b is vaporized in a heating chamber, (i) at a temperature between 200 and 800°C under ambient pressure to obtain a vapor of 0.001
2 hours, or (ii) 0.001 to 0.5 hours at 200 to 250° C. at ambient pressure from 50 mmHg in the presence of at least one oil fluid cracking catalyst consisting of alumina, silica and at least one other metal. , heating to decompose at least a portion thereof; (d) removing the decomposition product from the chamber as an effluent; and (e) recovering the decomposition product from the effluent. How to handle. 2. The method according to claim 1, wherein either or both of the above step (a)(ii) of removing the solvent and the above step (a)(iii) of adding an organic carrier are carried out. 3. The method according to claim 2, wherein the solvent in step (a)(ii) is acetone. 4. A process according to any of claims 1 to 3, wherein the decomposed vapor is cooled to 0° to obtain 25-75% organic liquid (based on the weight of the vapor). 5. The method of claim 1, wherein step (a)(iii) is carried out and the remaining resin contains less than 2% rubber.